Before we start talking about physics, though, I'd like you to share some of your experiences with roller coasters. Listen to a few students describe their favorite roller coasters. Point out some of the unique features of each coaster, such as hills and loops, that relate to the lesson. Does anyone know how roller coasters work?
For each pair of students, you will need: Context This is the second lesson in a three-lesson series about isotopes, radioactive decay, and the nucleus. The first lesson, Isotopes of Penniesintroduces the idea of isotopes. An Analogy to Carbon Datingis based on gathering evidence in the present and extrapolating it to the past.
To do this lesson and understand half-life and rates of radioactive decay, students should understand ratios and the multiplication of fractions, and be somewhat comfortable with probability.
Games with manipulative or computer simulations should help them in getting the idea of how a constant proportional rate of decay is consistent with declining measures that only gradually approach zero.
The mathematics of inferring backwards from measurements to age is not appropriate for most students.
They need only know that such calculations are possible. Benchmarks for Science Literacy, p. The exercise they will go through of predicting and successively counting the number of remaining "mark-side up" candies should help them understand that rates of decay of unstable nuclei can be measured; that the exact time that a certain nucleus will decay cannot be predicted; and that it takes a very large number of nuclei to find the rate of decay.
This lesson can be done in two, minute class periods. An Analogy to Carbon Dating, which can be done while students are flipping their candies.
In your planning, be sure to include time at the end of the lesson for students to post their data and share the class data. Planning Ahead Before the lesson, you will have to weigh out about 80 candies for each group of students.
If you count ten and weigh them, then multiply by 8, you will know how many grams of candy to weigh out for each group. Motivation To help students understand the history of radioactivity, have them go to Radioactivity: As students read about these scientists, ask them to think about the following questions: What important discovery was made by Wilhelm Roentgen?
What material did Antoine Becquerel work with in his own investigations of X rays? What did Becquerel discover through his experiments? What two elements were discovered by Marie and Pierre Curie?
Why is Ernest Rutherford considered the father of nuclear physics? List Rutherford's major achievements. Students can supplement this site with a visit to Isotopes Project. Once to that page, students should then go to the Isotope Discovery History, a graph of the number of known isotopes versus the date, and to the Chart of Aristotle and Plato found at the bottom of the pagewhich the site planners cleverly call "the first chart" of isotopes.
Radioactive decay, also known as radioactivity, is the spontaneous emission of radiation from the unstable nucleus of an atom. In your own words, what do we mean by nuclear decay? What do you think is emitted during radioactive decay? Have students go to the Isotopes Project website to look for more information about radioactive decay.
Have students look at the Glossary of Nuclear Science Terms for alpha and beta decay. Ask students to explain the terms in their own words.
What is the chance of getting heads on any flip?
What do we mean by random? After students have discussed these questions, tell them: This method of measuring a rate won't work for radioactive decay. We know that radioactive substances disintegrate at a known rate, however.
We call this rate the isotope's half-life.Isaac Physics a project designed to offer support and activities in physics problem solving to teachers and students from GCSE level through to university. Physics can help you determine what makes one hula hoop a winner and another a flop.
In this activity you will get to create your own hula hoops and investigate how their masses affect how they spin. Which do you think will spin better, a heavy hoop or a lighter one?
NOVA Teachers Resources listed by subject and type of resource: Physics Classroom Activities. rutadeltambor.com! The web site that teaches the basics of physics to everyone! Workshop Physics is a component of the Physics Suite––a collection of materials created by a group of educational reformers known as the Activity Based Physics Group.
The Physics Suite contains a broad array of curricular materials that are based on physics education research, including. Scientific American is the essential guide to the most awe-inspiring advances in science and technology, explaining how they change our understanding of the world and shape our lives.